Multifunctional hydrogel microparticles for biomedical sensing applications
Hiroaki Onoe, Member, IEEE
Department of Mechanical Engineering, Faculty of Science and Technology, Keio University, Yokohama, Japan
onoe@mech.keio.ac.jp
Abstract
Theranostics is a new medicine field, which integrates specific “diagnosis” and “therapy” into one system. This field is gathering attention because devices of theranostics can obtain in-body information and deliver therapeutic drugs at the same time. This property makes it possible to carry out appropriate therapy to the local point depending on the diagnostic results. Therefore, we can reduce the drug dose and mitigate the burden to the patients [1][2].
For the application of theranostics, multi-materials need to be contained in microdevices, such as hydrogel particles and micelles. However, currently reported theranostic microparticles contain multiple materials in a single location without any protection layer [3], since it is difficult to fabricate structure-controlled microparticles. This leads to a limitation of material combination and causes adhesion to medical tools and leakage of encapsulated materials. Even if the particles are compartmentalized and encapsulate different materials, multiple preparation steps are often required.
In this presentation, I introduce a one-step fabrication of core-shell Janus microparticles for the application of theranostics. Our microparticles can contain two functional hydrogels and encapsulate material in each hemisphere covered by the biocompatible hydrogel shell. The Janus structure together with the core-shell structure in one particle was formed by ejecting a pre-gel solution of mixed acrylate monomer with sodium alginate followed by photo-polymerization and ionic crosslinking, simultaneously. To demonstrate this concept works, microparticles that have a glucose detection hemisphere, a drug model (FITC-dextran) release hemisphere and an alginate protection layer was fabricated and examined by implanting these microparticles in biological tissue for transdermal detection of glucose and release of the encapsulated FITC-dextran driven by external stimuli.
[1] S. S. Kelkar and T. M. Reineke, “Theranostics: Combining imaging and therapy,” Bioconjug. Chem., vol. 22, no. 10, pp. 1879–1903, 2011.
[2] Y. Wang, M. S. Shim, N. S. Levinson, H. W. Sung, and Y. Xia, “Stimuli-responsive materials for controlled release of theranostic agents,” Adv. Funct. Mater., vol. 24, no. 27, pp. 4206–4220, 2014.
[3] D. Park, Y. Cho, S. H. Goh, and Y. Choi, “Hyaluronic acid-polypyrrole nanoparticles as pH-responsive theranostics,” Chem. Commun., vol. 50, no. 95, pp. 15014–15017, 2014.
Short Bio
Hiroaki Onoe, received his Ph.D. in Mechano-Informatics at The University of Tokyo under the supervision of Prof. Isao Shimoyama in 2006. Since 2007, he moved to University of California Berkeley and worked with Prof. Richard Mathies in Department of Chemistry as a visiting scholar. Since 2009, he began to work with Prof. Shoji Takeuchi at Institute of Industrial Science at The University of Tokyo as an assistant professor. Since 2014, he has joined to Keio University, Japan, and is now an associate professor in the Department of Mechanical Engineering. He received Igarashi Award from The Institute of Electrical Engineers of Japan in 2012, and The Young Scientist’s Prize, The Commendation for Science and Technology by the Minister of Education, Culture, Sports, Science and Technology in 2017. His research interests include microfluidics, biofabrication, functional materials and self-assembly technologies.